This invention relates to dispensers for beverages such as beer, soda, and the like and, more particularly, to apparatus usable with such dispensing units for automatically dispensing the beverage when a container is placed beneath the dispenser's tap and to stop dispensing when the container is withdrawn or after a predetermined period of time.
In baseball parks, football stadiums, and similar arenas, the sale of beer and soda is typically done by a concessionaire who contracts with the facility owner and makes his money based on the amount of product he can sell and the cost of selling it. Beer sales, for example, comprise a large part of the concessionaire's business. Consequently, it is most profitable for the concessionaire to dispense as much beer as he can sell. At events that have a large attendance, one drawback in doing this is that beer dispensers typically include manually operated taps which require the bartender to hold the tap open while the beer pours into the cup, mug, or whatever receptacle it is sold in. If the customer orders other things, hot dogs, pretzels, etc. with the beer, the seller has to wait until the beer is dispensed before they can fill the rest of the order. As a result, not as many customers can be served in the short period of time during which the bulk of sales are typically made; i.e. between innings, halftime. This not only effects the concessionaire's profits, but also causes spectators to be unhappy which could effect attendance.
In other settings such as taverns or restaurants, where beverage dispensers are similarly used, the same problem also occurs. Here, a waiter or waitress has to wait until the beverage is dispensed before he or she can do other necessary to complete the customer's service. While this may not ordinarily be a problem, at busy times, slow service means customer complaints and potential loss of business.
Automatic liquid dispensing or fluid flow control units have been previously developed. See, for example, U.S. Pat. Nos. 5,016,786, 5,007,560, 4,979,641, and 4,070,133, all of which are directed to beer dispensing; as well U.S. Pat. Nos. 4,984,314, 4,967,935, 4,953,236, 4,946,070, 4,915,347, 4,823,414, 4,670,010, and 4,111,243 which describe different control schemes for controlling the dispensing of other beverages or liquids. While the liquid dispensing apparatus described in these patents probably function to achieve their intended purpose, none necessarily solve the problems. With beer, for example, a major problem is the making of foam. Some proposed solutions involved having a solenoid through which the beer is flowed to automatically control its flow. However, it has been found that this creates more foaming than is desirable. Another proposed solution has been to leave the beer tap open at all times and automatically open and close the flow line upstream of the tap. This, however, allows dirt and bacteria into the tap and is therefore not acceptable. Additional proposals involve valves, but it has been found that beer leaves a film on the moving member of the valve which can cause the valve to stick, particularly if the dispenser is not used for some time.